Hello everyone. First time posting. Names Sterling. From the United States, currently in CA but i get around.

Been checking out the forum for a few months now since getting an 87 AT 4wd wagon.
Was blessed with a Tercel4WD.com sticker on the back window. I wasted no time coming here to start working on getting her up to snuff.
So it probably comes as no surprise that even after all the plentiful reading available here on the topic that there is ever more plentiful reasons to keep making posts about that darn thing that seems to be the first real stumbling block in restoring these amazingly cool little cars... That darn TVSV

Question: FSM states the TVSV will make the hot running switch at 154 degrees farenheit wherein port K will go through ports L & M.
yet the instructions say just to heat to above 154 degrees farenheit.
I pulled a TVSV out of a Chevy Nova on a whim while pulling apart the carb for springs and check balls (mine was missing 2 springs. the one under AAP aluminum plunger that would normally pop out when you first crack the carb open. and the one under the brass screw by it).
I did the test to it...only it didn't make the switch to hot mode fully until 164-ish farenheit.
so.... is 154 the final say on pass or fail? Or is 164 within tolerance?
and has anyone ever tried oiling one of these things?

Nice looking Tercel4wd. I doubt that difference will matter much, the normal operating temperature is well over that at 180 deg, so it just means a few min delay in the vac switching over to the other lines. it reaches operating temperature in under ten min of driving, so I can not see how that will matter much at all. all carburated cars "back in the day" were a bit baulkly and troublesome until they reach operating temperature, the Tercel is not different. We have been spoiled by EFI where is smoothly and seamlessly transmission from cold, to warm, to full temperature operation without any notice by the driver.

I make a habit of getting those TVSV when ever I find them in the wrecking yards or off parts cars going to a crusher. they were used on almost all of the Toyotas in the 80's that had carburetors. So far I got 6 good ones out of eight, but several were a bit "slow" to switch over, but I still consider them useable. I sprayed silicone lube into it to see if would help, it made no difference that I could tell. but it should help the seal, an internal vac leak in the TVSV wills till act like a vac leak, so I figured the silicone lube would help preserve the internal seal.

T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."Mark Twain

Just a little off topic, but the only time I have ever heard the word sinusoidal was here. Watch out for repleneration!

Well splat, perhaps you live out in the sticks somewhere, but it is a very important concept. You are indeed in need of more education. much of my engineering education was about understanding the properties of the sinusoidal phenomenon. it shows up everywhere in nature, machinery and particularly in automobiles. I mean how can you possibly know how to diagnose and fix most things on your customers cars if you do not know and understand about sinusoidal phenomenon?

The daily cycles of the sun, moon, the seasons, your daily sleep and wake cycles, including daily hormonal cycles, along with the spinning of your tires, the function of your radio, the intake, compression, power and exhaust cycles, the lifting of the valves, the operation fans, pumps and the suspension, all operate within the laws of sinusoidal physics.

Haha, I wish I was in the sticks. Someday camp will be home. I never heard that word before youtube. Apparently I have a deep understanding without even knowing it? A sinusoidal savant.. Does that "training" video count towards my continuing education?

Yes, you can use the functions of sinusoidal physics without knowing the name. Just like you can learn to ride a bicycle with out knowing anythi g about the complex dynamic stability that allows a bicycle to work at all. Have you ever consider how come you don't just fall over when riding a bike? It is actually a complex interaction, and the sinusoidal physics also show up there too.